Mert Caliskan recently posted blog article about JSF libraries performance.
I’ve downloaded and run all these examples on my local machine ( That is Intel Core2 Duo 2.4 Mhz, 4GB RAM, Fedora Core Linux 11, Apache Tomcat 6.0.18 with jdk 1.6.0_18 ). Though I got a similar results for RichFaces demo and Trinidad, PrimeFaces performs AJAX requests from 23 up to 80 milliseconds, with median about 40 milliseconds. Firebug results seem adequate because they are close to request processing time shown by the eclipse TCP/IP monitor.
There is FireBug console’s scrinshot:
Because even clean JSF page that contains only one form with one input field and submit button shows similar results that is about 20ms per request on the same environment, I do not see a much performance difference.